BUILT NOV 1971 THRU NOV 1973.POSSIBILITY THAT VEHICLES EQUIPPED WITH BACKREST HINGE FLANGE, THE EDGE COULD CAUSE ABNORMAL CHAFING OF THE SEAT BELTBUCKLE STRAP, WHICH RESTS AGAINST THE FLANGE WHEN OCCUPANT FASTEN SEAT BELT.(CORRECT BY INSPECTING AND PLACING A PROTECTIVE COVERING OVER FLANGE EDGE).